Femtosecond Pulse Delivery through Long Multimode Fiber Using Adaptive Pulse Synthesis

Abstract

We report on a delivery technique for 164-fs optical pulses with a peak power of 1.1 kW through a long multimode optical fiber and a glass block using an adaptive pulse-shaping feedback loop. We used two devices to optimize the input pulse; a pulse stretcher and a pulse shaper. 382-ps chirped pulses are compressed to 370-fs pulses at the output end of a glass block joined to a standard graded-index multimode fiber, 96 m in length and with a core diameter of 50 µm (the output end of the system). The adaptive pulse shaper compensates for the remaining high-order phase dispersion, which results in 164-fs pulses at the output end of the system. Our work shows that an adaptive pulse synthesis technique provides a powerful and convenient technique for programmable fiber dispersion compensation over a broad optical bandwidth.